An example of such an industrial vehicle is an industrial vehicle such as a power-shovel-type industrial vehicle that is capable of excavating a ground surface (see Japanese Laid-open Patent Application No. 2005-273145 for example). In this industrial vehicle, a revolving body is provided that is supported on a traveling body so as to be able to rotate (i.e., turn horizontally) about an axis that extends in the vertical direction, and an implement (power shovel device) having a pivoting boom is attached to the front part of the revolving body. An engine room covered by a hood and accommodating an engine is provided to the rear part of the revolving body. Also provided along with the engine are a radiator, an oil cooler, a hydraulic pump, and also a hydraulic fluid tank for storing the hydraulic fluid of the hydraulic device, a revolving motor for turning the revolving body, and other components. A counterweight is also provided to the rear part of the revolving body in order to balance the weight of the power shovel device provided to the front part of the revolving body, and to enable the power shovel device and the revolving body to stably operate.
In conventional designs, the power source of such an industrial vehicle as the one described above is an engine (internal combustion engine), the traveling body is caused to travel by the engine, and a hydraulic pump for supplying oil pressure for operating the power shovel device, the revolving motor, or the like is also driven by the engine. There have also recently been industrial vehicles in which, out of consideration for effects on the surrounding environment, the hydraulic pump is driven by an electric motor rather than the engine to operate the implement, so as not to emit exhaust gas or make a large amount of noise. In this case, an electric motor provided inside the revolving body is connected to a commercial power supply or a power generator via a power supply cable, and thus receives electrical power.